Try to turn the compressor by hand. It should be possible to turn it around. It should turn around smoothly, without any ‘hiccups’ (be sure to completely shut down the air compressor!). Check the isolation of the motor winding.
[pdf] It should turn around smoothly, without any 'hickups' (be sure to completely shut down the air compressor!). Check the isolation of the motor windings. Should be in the mage-ohms (you need an isolation tester / high voltage ohm meter for this). Check the voltage when the compressor is running.
[pdf] Each screw machine must be equipped with a gas storage tank and, if needed, auxiliary equipment such as a cold dryer and a filter. The installation requirements are as follows: A) The installation sequence of supporting equipment is: “air compressor → gas tank → gas-water separator → cold dryer.”
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